Method of spraying molten pulverized quartz or enamel mixtures



yPatenteotitov. 22, iigA V.

unirse STATES PATENT' orlucs METHOD OF SPRAYING MOLTEN PULVR- IZED QUARTZ R, ENAMEL MIXTURES My invention relates. to method of spraying I molten pulverized quartz or enamel mixtures and has for its principal object, to provide a relatively simple and easily practiced method for applying quartz or enamel mixtures to surfaces and various articles and the practice of which improved method, may be accomplished with a material saving of time, labor and consequent expense. f

` My improved method involves the delivery of finely pulverized quartz or enamel mixtures by means of air under pressure, into a chamber where it is melted under the heat developed by the combustion of gases `such as oxygen and acetylene and the molten quartz or enamel mixtures being discharged from the melting chamber directly onto the surface` or article to' be coated.

It has heretofore been the general practice in the art of enameling to dust, dip, spray or slush articles to be enameled and then place same in ovens to be baked or glazed. In the enameling of bath tubs, sinks, sheet iron and the like, the general practice is, to preheat the articles to be enameledand then to spray or dust the enameling powder thereupon and the article afterwards heat treated or baked, to iix the enamel coating. My improved prooess'enables molten quartz or enamel mixtures to be sprayed directly onto various articles such as bath tubs, sinks, sheet metal, kitchen utensils, stoves, refrigerators, automobile parts, signs, wall tile and the like without involving heat treatment ,or baking of the articles after the glaze or enamel has been applie to the surfaces thereof.

Further, my improved process enables the bottoms of vessels to be sprayed with a specially prepared nely pulverized quartz, to form a protective coating that will prevent the development of rust and also prevent barnacles and .the like,

from attaching themselves to the surfaces.

Further, my improved method may be advantageously employed in spraying molten quartz onto wire cloth to provide a sheet or panel that Vwill admit infra-red visible and ultraviolet rays Fig. 3 is a cross section taken on the line 3--3 of Fig.. 1. v

Fig. 4 is a sectional view of a form of spray gun having means for preheating the powdered or pulverized quartz or enamel mixtures before the same enter the melting chamber.

Referring byfnurnerals to the accompanying drawing which illustrates aA simple and convenient form of spray gun that may be used in practicing my improved method, I0 designates` a handle which may be formed of wood, metal or composition and which is shaped somewhat similar to the handle of a pistollin order -that the device may be conveniently held and manipulated. Removably mounted on the upper end ofthe handle, is a substantially cylindrical housing II and projecting from the -forward end of. said housing, is'a short tubular nozzle l2.

Disposed Within the housing I I and detachably applied to the handle I0, is a nozzle I3 provided with an axial bore I4 that communicates with a duct I5 that passes lengthwise through the central portion of handle IIJ.

Connected to the lower end of the handle l0 and communicating with bore I5, is a valve I6 and connected thereto is a exible tube -I'I that leads fromthe pulverized quartz or enamel mixture source of supply.

The pulverized material is forced through tube y I1 and ducts I4 and I5 by compressed air and the flow of the powdered material may be controlled by proper manipulation of valve IB.

l 'I'he forward end of nozzle I3 terminates a short distance inwardly from the inner end'of nozzle I2 and port I4 is in direct axial alignment with said-nozzle I2.

Arranged for sliding movement through the intermediate portion of handle IIJ, is a valve I8 that controls the flow of pulverizedmaterial through duct I5 and said valve is normally maintained in closed position by an expansive coil spring I9.

A trigger 20 ispivotally mounted on handlel I0 with the lower portion of said trigger bearing against the projecting endl ofvalve I8, `thus providing means for conveniently opening valve I8 while the spray gun is held in the hand.

Formed throughhandle l0 isa duct 2l and l seated in the lower end of the handle and communicating with said duct, is a valve 22.

Connected to valve 22 is a flexible tube '23 that leads to a source of acetylene supply. In the upper end of the handle Il), the duct 2| communicates by means of branch ducts 24 with ducts 25 that are formed through nozzle I 2 so that a plurality of jets of acetylene are discharged from the forward end of nozzle Il.

A duct 26 passes lengthwise through handle IU and seated in the lower end of said handle and communicating with said duct is a valve 21, to which is connected av iiexible tube 28 and the latter leading to a suitable source of oxygen Supply.

The upper end of duct 28 communicates 'by means of branch ducts 29 with ducts 30, that are formed through the nozzle Il.

The ducts through which the acetylene gas passes are preferably alternately arranged with the ducts 30 through which the oxygen passes and all of said ducts are disposed about the central duct I4 through which the pulverized quartz or enamel mixtures pass.

' In Fig. 4 I have illustrated a spray gun structure having means for'preheating the quartz or enamel mixtures before the same enter the melting chamber and in this construction the upper end of duct I5 is connected outside the housing Il to one end oi' a tube I5* that is coiled around the housing II and the other end of said tube communicates with duct Il in the nozzle Il.

In practicing my improved method with the apparatus disclosed pulverized quartz or enamel mixtures pass from the source of supply through flexible tube I1, duct I5 and bore Il, said pulverized material being under air pressure and the volume ilow of material to the spray gun, being regulated by means of valve I0.

'I'he flow of the pulverized materialthrough the spray gun is controlled by manual operation of valve Il.

Simultaneous with the discharge of pulverized material from the spray gun, acetylenegas and oxygen or other combustible gases capable of producing relatively high degrees of heat, pass from their sources of supply through tubes 23 and 2l,

v ducts 2ll and 2t, thence through the branch ducts nozzlel.

These gases are ignited at the discharge end o! nozzle I8, thereby producing a blow name having relatively high degrees otheat and as a result,

.the tineLv powdered or pulverized quarts of enamel mixtures discharging from the end of bore IB are instantly melted and in such condition are forcibly blown through nozzle I2 against the surface that is to be coated.

Due to the fact that the quartz or enamel mixtures are specially prepared and nely pulverized before being delivered to the spray gun, said material will melt instantly as it discharges from the nozzle of the gun and which nozzle also discharges the acetylene and oxygen gases that are ignited within the melting chamber and which pass therefrom outwardly through nozzle I2.

In .the construction illustrated in Fig. 4, the pulverized material in passing through the coil IB, is4 effectively preheated before being discharged from th nozzle Il and such preheating of the material enables lower temperatures to be utilized in melting. the pulverized material.

Obviously various types and forms of spray guns other than the one herein shown and described may be advantageously employed for simultaneously melting and spraying pulverized quartz or enamel mixtures onto the surfaces to be coated. v

Thus it will be seen that I have provided a relatively simple and easily practiced method of and apparatus for melting pulverized quartz and enamel mixtures and spraying the same directly onto the articles or surfaces to be coated.

I claim as my invention:

' The herein described method of spraying molten pulverized coating mixtures which consist in producing a substantially circular blow-flame within a chamber having anoutlet opening directly in front of and in alignment with said flame, causing the pulverized coating mixture to flow axially through the circular blow-name so that it is pre' heated by the heat developed by said blow-flame within said chamber, causing the pre-heated pulverized mixture to flow with the circular blowflame through the chamber toward the outlet opening, so as to melt said pulverized coating mixture and causing the same in moltenl condition and said circular name to discharge through said outlet openinz so that the molten mixture is delivered directly onto the surface to be coated.

AIIIARL Il'. CALLAN 

